This study is directed toward gaining an understanding of developmentally-regulated programmed cell death in the Drosophila retina. While considerable data is accumulating regarding the molecular machinery of programmed cell death, little is known about how cell death decisions are made during development. The Drosophila retina is an excellent system for addressing these questions. It is a highly ordered tissue in which even minute changes in cell number are easily detected and which is absolutely dependent on selective cell death for proper patterning. Recent data described herein suggest that the Drosophila p38 Map kinases are involved in the regulation of retinal cell death. The specific goal of this work is to define the role of p38 in this process and to place it into the context of what is currently known about regulation of cell death decisions in the fly retina.